Conventionally, a power conversion device has been known that cuts off an electrical path when a power semiconductor element short-circuits (see, for example, Patent Document 1). In this power conversion device, the power semiconductor element is connected with a positive-polarity terminal via a thin metallic wire, and is connected with a negative-polarity terminal via a thin metallic wire.
In this structure, if the power semiconductor element short-circuits, an overcurrent, which is several to several dozen times greater than the rated current, flows to fuse the thin metallic wire by self-heating. Therefore, it is possible to promptly cut off the electrical path when the power semiconductor element short-circuits, and to prevent the overcurrent from circulating.